<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>justify-content</title><!--横轴对齐方式-->
    <style type="text/css">
        .box{
            display:flex ;
            height: 50px;
            width: 200px;
            border-radius: 5px;
            background-color: #eee;
        }
        .box div{
            margin: 5px;
            padding: 10px;
            border-radius: 5px;
            background-color: #aaa;
            text-align:center;
        }
        #div1{  justify-content: flex-start;  }
        #div2{justify-content: flex-end;}
        #div3{justify-content: center;}
        #div4{justify-content: space-between;}
        #div5{justify-content: space-around;}
    </style>
</head>
<body>
<h2>flex-start</h2>
<div class="box" id="div1">
    <div>1</div>
    <div>2</div>
    <div>3</div>
</div>
<h2>flex-end</h2>
<div class="box" id="div2">
    <div>1</div>
    <div>2</div>
    <div>3</div>
</div>
<h2>center</h2>
<div class="box" id="div3">
    <div>1</div>
    <div>2</div>
    <div>3</div>
</div>
<h2>space-between</h2>
<div class="box" id="div4">
    <div>1</div>
    <div>2</div>
    <div>3</div>
</div>
<h2>space-around</h2>
<div class="box" id="div5">
    <div>1</div>
    <div>2</div>
    <div>3</div>
</div>
</body>
</html>